The performance of a combustion engine can be improved utilizing a turbocharger including a turbine side and a compressor side. Improvement in the emissions from such a combustion engine can be achieved with exhaust gas recirculation. However, for low pressure exhaust gas recirculation systems, high flow rates of the exhaust gas being recirculated can lead to high compressor inlet temperatures. An exhaust gas cooler may be positioned to reduce the temperature of the exhaust gas prior to the compressor inlet. However, such systems can lead to condensation of water vapor in the exhaust gas and wherein the resultant water droplets damage the compressor wheel which is spinning at a relatively high rpm.
High pressure applications of exhaust gas recirculation provide a recirculation flow path for the exhaust gas before the exhaust goes through a turbocharger (if present). Coolers have been used in such high pressure recirculation systems, but under certain circumstances such systems may produce undesirable constituents in the gas or lead to undesirable engine performance.